Embodiments of this disclosure relate generally to a manufacturing device, and more particularly, to a portable, Computer Numerical Control (CNC) machine that moves along assembly surfaces.
It may be desirable to locate, with a certain degree of accuracy and specificity, locations in a blind area of a working surface. For example, if it is desired to affix together two portions of a structure, where only an outside surface is visible to a work person, it may be difficult to precisely and reproducibly place a fastener between the two portions. This may be particularly relevant in regards to aircraft where the skin of the aircraft may be placed over an internal frame structure and affixed thereto. In the above case, once the skin is in place, it may be difficult to locate a fastener that may first go through the skin to be affixed to the internal structure of the aircraft. This situation arises in other construction and manufacturing instances as well.
Presently, one solution has been the attempt to back drill from inside the structure. In the above aircraft scenario, it may be a common practice to back drill the wing skin holes from inside the wing using pre-drilled holes in ribs and spars as the templates. However, this may lead to off-angle holes and subsequent required rework.
During back drilling, a work person physically places themselves inside the structure, often in areas where spacing may be tight. The person then drills through the sub-structure and through the skin. This, however, may create impreciseness in the holes. Furthermore, it may be hard on the work person who may have crawl or reach into small areas to create the holes.
Backmarkers may also be used in the aircraft industry to transfer holes from the understructure to the outside surface. Backmarkers may consist of a long split piece of thin metal with a pin on one side and a hole on the other that are in alignment. The pin side may be slipped under the skin to line up with a pilot hole in the understructure, and a pilot hole is drilled into the outer skin. However, deflection of the split plates and the difficulty of installing the device on thick parts may limit the use to thin areas near the edge of the skin.
Another method may be to use a probe or locating device to determine a precise position on the skin. The probe is generally programmed with locations in three dimensional space. When a surface is placed within reach of the probe, the probe can determine the location of a point which the probe touches. This, however, requires an extensive pre-programming and precise placement of the surface to be probed. Using such special orientation probes increases time and manufacturing costs for many applications.
Therefore, it would be desirable to provide a system and method that overcomes the above.